Splitting rhubarb?

I'm not an expert on rhubarb but what i would do is cut off with a spade a couple of chunks with a growth bud and leaves and a good piece of root. Make sure there are no bits of bindweed in the roots. Pot up or plant where you would like them. You wouldn't be able to take anything off them next year but should be good for the following. Your current plant should be still producing next year but as long as the new plants are thriving, you could deal with the old plant and the bind weed this time next year.

I've got some old rhubarb plants that are overgrown and have had nothing off them for a couple of years. I've just taken 2 chunks out of the patch before they disappear completely and potted one up and put the other in in a corner. they are both surviving even though the wind took the only leaf off one of them.